1. Technical Field
The present invention relates to sealing members, liquid ejecting heads, and liquid ejecting apparatuses.
2. Related Art
An ink jet recording head that ejects ink droplets can be given as a representative example of a liquid ejecting head that ejects liquid droplets. An ink jet recording head that, for example, includes a main head unit that ejects ink droplets from nozzle openings and a head holder, and in which is provided a sealing member that forms a seal between the respective flow channels in the main head unit and the head holder, has been proposed (for example, see JP-A-2008-238752, JP-A-2009-214368, and JP-A-2010-079649).
It is necessary for the sealing member to be positioned at a comparatively high level of precision between the main head unit and the head holder. Specifically, it is necessary for the communication openings of the sealing member to be positioned at a comparatively high level of precision relative to the liquid flow channels of the main head unit and the head holder. To position the sealing member at a high level of precision in such a manner, a reference hole into which a positioning pin is inserted is provided in the sealing member, and the positioning pin is positioned in the head holder or the main head unit, after which the sealing member is positioned relative to the head holder or the main head unit using the positioning pin; the direction of the sealing member in the horizontal plane is then fixed.
However, there is a problem in that the farther away the communication hole of the sealing member is from the reference hole, the positional precision of the sealing member and the precision with which the shape of the sealing member is maintained drops due to warping or the like of the sealing member, and thus the sealing member cannot be positioned relative to the other members with a high level of precision. If the communication opening of the sealing member then shifts from the liquid flow channels of the other members, the sealing property between the liquid flow channels that communicate with the communication opening drops, which can cause problems such as the risk of liquid leaks and the like occurring. In addition, if the communication opening shifts from the liquid flow channels, it is easier for bubbles to accumulate in the shifted sealing member; bubbles that have accumulated and grown may then be ejected from the nozzles, resulting in missing dots. Furthermore, as a result of the position of the communication opening shifting, there is a risk that the flow channel resistance of the liquid that flows within the liquid flow channel will change, leading to ejection malfunctions.
Further still, it is necessary to stretch the sealing member, which is provided with a plurality of communication openings, when positioning the respective communication openings, and at this time, the same problem as mentioned earlier will arise due to the communication openings deforming due to the stretching of the sealing member, the positions of the communication holes shifting from the positioning pins (reference holes), and so on.
It should be noted that these problems are not limited to ink jet recording heads, and are also present in other liquid ejecting apparatuses that eject liquids aside from ink. Furthermore, these problems are not limited to sealing members used in ink jet recording heads, and are also generally present in sealing members that are interposed between any given members.